Hair styling device

ABSTRACT

A hair styling device includes a base; and a plurality of pins having respective first ends connected to a first side of the base, and spaced from each other. The base and the pins are produced from a single-layer flexible workpiece. Two of the plurality of pins are connected to each other at respective second ends opposite to the first ends, thereby forming a bistable mechanism that is capable of switching between concave-convex positions in response to an external force, and at least another two of the plurality of pins have free second ends opposite to the first ends, thereby forming a second branch layered from the first branch. The first branch is switched to a concave position relative to the second branch to create a space for receiving or releasing hair, and switched to a convex position relative to the second branch to close the space for securing hair.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a nonprovisional application claiming benefitfrom a prior-filed provisional application bearing a Ser. No. 62/661,593and filed Apr. 23, 2018, the entity of which is incorporated herein forreference.

FIELD OF THE INVENTION

The present invention relates to a hair styling device, and moreparticularly to a hair styling device made of a flexible workpiece, andswitching between a working state and a preparatory state with the statechange of the flexible workpiece.

BACKGROUND OF THE INVENTION

A conventional hair clip, which is so-called as a snap clip, includes anupper metal piece 11 and a lower metal piece 12. The upper metal piece11 consists of two metal pins connected together at one end, therebyforming a bistable mechanism that is capable of switching betweenconcave-convex positions so as to render an open (preparatory) state anda closed (working or standby) state relative to the lower metal piece12. When the upper metal piece 11 is switched to be the open position byforcing the upper metal piece 11 to become concave, as shown in FIG. 1A,a hair portion may enter the space between the upper metal piece 11 andlower metal piece 12. Then the metal piece 11 is forced to becomeconvex, as shown in FIG. 1B, and close the space together with the lowermetal piece 12 so as to clamp the hair portion inside. Afterwards, theupper metal piece 11 can be forced to open again for releasing the harportion.

Since the lower metal piece 12 of such a snap clip is implemented with asingle metal strip, it is likely to slide off hair. Another conventionalsnap clip as shown in FIG. 1C is thus developed to ameliorate theunstable clamping problem. The snap clip includes an upper metal piece11 similar to that shown in FIG. 1A, and a widened lower metal piece 13.The widened lower metal piece 13 is made hollow for reducing weight tominimize the gravity effect on sliding off hair. Even so, the clampingforce of such a snap clip is still insufficient for stabilizing the clipon hair.

U.S. Pat. No. 7,373,940 discloses a snap clip as shown in FIG. 2A andFIG. 2B, which includes an upper metal piece 21, a lower metal piece 22,and a living hinge 23 between the upper metal piece 21 and the lowermetal piece 22. Likewise, the upper metal piece 21 consists of two metalpins connected together at one end, thereby forming a bistable mechanismthat is capable of switching between concave-convex positions so as torender an open (preparatory) state and a closed (working or standby)state relative to the lower metal piece 22. The lower metal piece 22 isformed under the upper metal piece 21 and has enhanced clamping force asmore metal strips are involved for clamping hair. In addition, as thethree metal strips are separate at the open end and have gaps inbetween, hair may enter the gaps and be hindered from relative movementto the metal strips due to interaction with the metal strips. Such asnap clip, however, suffers from the gravity effect since the snap clipis formed with a larger workpiece to be folded at a position of theliving hinge 23 to define the upper metal piece 21 and the lower metalpiece 22. The larger workpiece means a higher cost, and the foldingoperation means an additional procedure requiring aligning precision.Such a snap clip further suffers from an inherent gap between the uppermetal piece 21 and the lower metal piece 22 as a result of folding theworkpiece. The gap would adversely affect the clamping tightness.Moreover, the flexibility of the living hinge might adversely affect thebistable switching performance.

SUMMARY OF THE INVENTION

Therefore, there is a need to design a hair styling device, which has animproved clamping performance.

According to the present invention, a hair styling device includes abase; and a plurality of pins having respective first ends connected toa first side of the base, and spaced from each other. The base and theplurality of pins are produced from a single-layer flexible workpiece.At least two of the plurality of pins are connected to each other atrespective second ends opposite to the first ends, thereby forming abistable mechanism that is capable of switching between concave-convexpositions in response to an external force, and at least another two ofthe plurality of pins have free second ends opposite to the first ends,thereby forming a second branch layered from the first branch. The firstbranch is switched to a concave position relative to the second branchto create a space for receiving or releasing hair, and switched to aconvex position relative to the second branch to close the space forsecuring hair.

The pins forming the second branch may be all disposed between the pinsforming the first branch. Alternatively, some of the pins forming thesecond branch are disposed between the pins forming the first branch,and the others are disposed outside the pins forming the first branch.

Shapes of the pins forming the second branch may be selected from lines,curves, waves, or a combination thereof, or any other suitable shape.

In an embodiment, adjacent two of the pins forming the second branchhave respective lateral extensive structures protruding toward eachother, and the lateral extensive structures are deformable to retain aresilient force when compressed by hair entering the space between thefirst branch and the second branch, thereby further securing hair in thehair styling device. Preferably, the lateral extensive structures arethinner than the pins where they are connected, and have conformableshapes to each other.

In an embodiment, the hair styling device further comprises mini-postsprotruding from a specified surface of the pins forming the secondbranch and/or mini-posts protruding from a specified surface of the pinsforming the first branch. Preferably, the specified surface of the pinsforming the second branch is the surface facing the first branch, andthe specified surface of the pins forming the first branch is thesurface facing the second branch.

The single-layer flexible workpiece for producing a hair styling deviceaccording to the present invention is made of metal, plastic or paper.

The present invention also provides a method for producing a hairstyling device as described above. The method comprises providing ametal sheet; stamping the metal sheet to obtain the single-layerflexible workpiece defining with the base and the plurality of pins; andconnecting the at least two pins for forming the first branch.

The present invention further provides a method for producing a hairstyling device as described above. The method comprises: providing aninjection-molded plastic sheet as the single-layer flexible workpiecedefining with the base and the plurality of pins; and connecting the atleast two pins for forming the first branch.

The present invention further provides a method for producing a hairstyling device as described above. The method comprises: providing a 3Dprinted material sheet as the single-layer flexible workpiece definingwith the base and the plurality of pin; and connecting the at least twopins for forming the first branch.

BRIEF DESCRIPTION OF THE DRAWINGS

The above contents of the present invention will become more readilyapparent to those ordinarily skilled in the art after reviewing thefollowing detailed description and accompanying drawings, in which:

FIGS. 1A and 1B are schematic diagrams illustrating two operationalstates of a conventional hair styling device;

FIG. 1C is a schematic diagram illustrating another conventional hairstyling device;

FIGS. 2A and 2B are schematic diagrams illustrating two operationalstates of still another hair styling device;

FIG. 3A is a schematic top view of a workpiece for forming a hairstyling device according to an embodiment of the present invention;

FIG. 3B is a schematic top view of the hair styling device produced fromthe workpiece of FIG. 3A;

FIGS. 3C and 3D are schematic side views illustrating two operationalstates of the hair styling device of FIG. 3B;

FIGS. 4A-4D are schematic top views illustrating variations of pins ofhair styling devices according to the present invention;

FIG. 5A is a schematic top view of a workpiece for forming a hairstyling device according to another embodiment of the present invention;

FIG. 5B is a schematic top view of the hair styling device produced fromthe workpiece of FIG. 5A;

FIG. 6A is a schematic top view of a workpiece for forming a hairstyling device according to an embodiment of the present invention;

FIG. 6B is a schematic top view of the hair styling device produced fromthe workpiece of FIG. 6A;

FIG. 7A is a schematic top view of a workpiece for forming a hairstyling device according to an embodiment of the present invention;

FIG. 7B is a schematic top view of the hair styling device produced fromthe workpiece of FIG. 7A;

FIGS. 7C and 7D are schematic side views illustrating two operationalstates of an example modified from the hair styling device of FIG. 7B;

FIGS. 7E and 7F are schematic side views illustrating two operationalstates of another example modified from the hair styling device of FIG.7B;

FIG. 8A is a schematic top view of a workpiece for forming a hairstyling device according to an embodiment of the present invention;

FIG. 8B is a schematic top view of the hair styling device produced fromthe workpiece of FIG. 8A;

FIGS. 8C and 8D are schematic side views illustrating two operationalstates of the hair styling device of FIG. 8B;

FIG. 9 is a schematic diagram illustrating a hair styling deviceaccording to an embodiment of the present invention, which is producedfrom an injection-molded workpiece;

FIG. 10 is a schematic top view of a hair styling device according to anembodiment of the present invention, which is produced from aninjection-molded workpiece; and

FIG. 11 is a schematic diagram illustrating a hair styling deviceaccording to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention will now be described more specifically withreference to the following embodiments. It is to be noted that thefollowing descriptions of preferred embodiments of this invention arepresented herein for purpose of illustration and description only; it isnot intended to be exhaustive or to be limited to the precise formdisclosed.

FIGS. 3A and 3B schematically illustrate an embodiment of a hair stylingdevice according to the present invention, wherein FIG. 3A schematicallyillustrates a workpiece and FIG. 3B schematically illustrates a hairstyling device produced from the workpiece of FIG. 3A. The workpiece isa flexible material sheet, which is integrally formed and configured asa single layer. The term “flexible” material sheet used herein andhereinafter means the material sheet is deformable when being appliedwith a proper intensity of external force, and restorable to itsoriginal state when the external force is removed. The flexible materialsheet also includes a sheet of relative rigid material, which is thinenough to be elastically deformable. The workpiece is defined with abase 31 and four pins 301, 302, 303 and 304 commonly coupled to the base31. Respective ends 3010 and 3040 of the pins 301 and 304 are connectedto define a first branch 310. The structure of the first branch 310renders a bistable mechanism that is capable of switching betweenconcave-convex positions in response to an external force. The pins 302and 303 have free ends 3020 and 3030, extending in a directionsubstantially the same as the pins 301 and 304, and defining a secondbranch 320 layered from the first branch 310. The second branch 320, asa whole, is substantially flat, and does not involve any state changewhen the hair styling device is operated in different states.Accordingly, a hair styling device as shown in FIG. 3B can be produced.For example, the hair styling device may be used as a snap clip. In thisembodiment, the pins 301-304 of the workpiece are spaced from eachother, and the pins 302 and 303 forming the second branch 320 aredisposed between the pines 301 and 304 forming the first branch 310.Furthermore, the length of the pins 302 and 303 are shorter than that ofthe pines 301 and 304. Therefore, when the hair styling device isproduced as shown in FIG. 3B, the second branch 320 is completelysurrounded by the first branch 310 in a top view, while the secondbranch 320 is in a different layer from the first branch 310 in a sideelevational view.

The use of the hair styling device is briefly exemplified herein. First,force the first branch 310 to switch to a concave position, asillustrated in FIG. 3C, thereby creating an open space 312 together withthe second branch 320. Insert the pins 302 and 303 into hair to havehair enter the hair styling device from the open space 312. Then forcethe first branch 310 to switch to a convex position, as illustrated inFIG. 3D, thereby closing the opening space 312 together with the secondbranch 320 for securing hair therein. For releasing hair, force thefirst branch 310 to switch to the concave position again.

In the embodiment illustrated in FIG. 3, the pins 301-304 are linear andflat. In other embodiments, one or more of the pins may be independentlymodified to have alternative configurations according to practicalrequirements. FIGS. 4A-4D schematically illustrate examples ofvariations of pins according to the present invention. For example, asshown in FIG. 4A, the pins 302 and 303 are curved. In the example shownin FIG. 4B, the pins 302 and 303 are made wavy in a direction normal tothe plane of the second branch 320 and/or in a directional conformal tothe plane of the second branch 320. This embodiment is advantageous inenhancing the frictional force with hair clamped therein and thusimproving clamping performance. Referring to FIG. 4C and FIG. 4D, forfurther stabling the hair styling device in hair, a lateral extensivestructure 321 may be provided at one or both sides of the pin. Thelateral extensive structure 321 is advantageous in enlarging theinteraction area with hair. It is to be noted that the term “lateral”extensive structure means the structure 321 extends from the pin 302 or303 in a direction substantially conformal to the plane of the secondbranch 320. The lateral extensive structure 321 may extend a littleupper or lower relative to the plane of the second branch 320 as long asthe function of the lateral extensive structure 321 can be conducted.Preferably, the lateral extensive structure 321 is thinner than the pinthat it is connected to. The thin and flexible feature of the lateralextensive structure provides an elastically deformable feature to thehair styling device so as to further secure the clamped hair.

FIGS. 5A and 5B schematically illustrate an embodiment of a hair stylingdevice according to the present invention, wherein FIG. 5A schematicallyillustrates a workpiece and FIG. 5B schematically illustrates a hairstyling device produced from the workpiece of FIG. 5A. The workpiece isa flexible material sheet, which is integrally formed and configured asa single layer. The workpiece is defined with a base 51 and six pins501, 502, 503, 504, 505 and 506 commonly coupled to the base 51.Respective ends 5020 and 5050 of the pins 502 and 505 are connected todefine a first branch 510. The structure of the first branch 510 rendersa bistable mechanism that is capable of switching between concave-convexpositions in response to an external force. The pins 501, 503, 504 and506 have free ends 5010, 5030, 5040 and 5060, extending in a directionsubstantially the same as the pins 502 and 505, and defining a secondbranch 520 layered from the first branch 510. The second branch 520, asa whole, is substantially flat, and does not involve any state changewhen the hair styling device is operated in different states.Accordingly, a hair styling device as shown in FIG. 5B can be produced.For example, the hair styling device may be used as a snap clip. In thisembodiment, the pins 501-506 of the workpiece are spaced from eachother, the pins 503 and 504 forming the second branch 520 are disposedbetween the pines 501 and 505 forming the first branch 510, and the pins501 and 506 forming the second branch 520 are disposed outside the pines501 and 505 forming the first branch 510. Furthermore, the length of thepins 503 and 504 are shorter than that of the pines 502 and 505, whilethe length of the pins 501 and 506 are longer than that of the pines 502and 505. Therefore, when the hair styling device is produced as shown inFIG. 5B, the second branch 520 is partially distributed inside andpartially distributed outside the first branch 510 in a top view, whilethe second branch 520 is in a different layer from the first branch 510in a side elevational view. It is to be noted that the number and lengthof the pins forming the second branch 520 in each of the embodimentsdescribed herein, hereinbefore and hereinafter may properly changedepending on practical requirements. By simultaneously inserting thefour pins 501, 503, 504 and 506 into hair, the hair styling device canbe used in more stable way. Furthermore, a variety of modifications tothe pins, e.g. those shown in FIG. 4, can be made for improved functionsand/or decoration purposes.

FIGS. 6A and 6B schematically illustrate an embodiment of a hair stylingdevice according to the present invention, wherein FIG. 6A schematicallyillustrates a workpiece and FIG. 6B schematically illustrates a hairstyling device produced from the workpiece of FIG. 6A. The workpiece isa flexible material sheet, which is integrally formed and configured asa single layer. The workpiece is defined with a base 61 and nine pins601, 602, 603, 604, 605, 606, 607, 608 and 609 commonly coupled to thebase 61. Respective ends 6030 and 6070 of the pins 603 and 607 areconnected to define a first branch 610. The structure of the firstbranch 610 renders a bistable mechanism that is capable of switchingbetween concave-convex positions in response to an external force. Thepins 601, 602, 604, 605, 606, 608 and 609 have free ends 6010, 6020,6040, 6050, 6060, 6080 and 6090, extending in a direction substantiallythe same as the pins 603 and 607, and defining a second branch 620layered from the first branch 610. The second branch 620, as a whole, issubstantially flat, and does not involve any state change when the hairstyling device is operated in different states. Accordingly, a hairstyling device as shown in FIG. 6B can be produced. For example, thehair styling device may be used as a snap clip. In this embodiment, thepins 601-609 of the workpiece are spaced from each other, the pins 604,605 and 606 forming the second branch 620 are disposed between the pines603 and 607 forming the first branch 610, and the pins 601, 602, 608 and609 forming the second branch 620 are disposed outside the pines 603 and607 forming the first branch 610. Therefore, when the hair stylingdevice is produced as shown in FIG. 6B, the second branch 620 ispartially distributed inside and partially distributed outside the firstbranch 610 in a top view, while the second branch 620 is in a differentlayer from the first branch 610 in a side elevational view. Bysimultaneously inserting the seven pins 601, 602, 604, 605, 606, 608 and609 into hair, the hair styling device can be used in more stable way,and function like a comb clip. Furthermore, a variety of modificationsto the pins, e.g. those shown in FIG. 4, can be made for improvedfunctions and/or decoration purposes. The hair styling device in thisembodiment further includes lateral extensive structures 621. Thelateral extensive structures 621 extending from a pair of adjacent pinsextend into a gap between the adjacent pins. The lateral extensivestructures are thinner than the pins where they are connected, and haveconformable shapes to each other. The lateral extensive structures 621are deformable to retain a resilient force when compressed by hairentering the space between the first branch 610 and the second branch620, thereby further securing hair in the hair styling device.

FIGS. 7A and 7B schematically illustrate an embodiment of a hair stylingdevice according to the present invention, wherein FIG. 7A schematicallyillustrates a workpiece and FIG. 7B schematically illustrates a hairstyling device produced from the workpiece of FIG. 7A. The workpiece isa flexible material sheet, which is integrally formed and configured asa single layer. The workpiece is defined with a base 71 and seven pins701, 702, 703, 704, 705, 706, 707, 708 and 709 commonly coupled to thebase 71. Respective ends 7020 and 7060 of the pins 702 and 706 areconnected to define a first branch 710. The structure of the firstbranch 710 renders a bistable mechanism that is capable of switchingbetween concave-convex positions in response to an external force. Thepins 701, 703, 704, 705 and 707 have free ends 7010, 7030, 7040, 7050and 7070, extending in a direction substantially the same as the pins702 and 706, and defining a second branch 720 layered from the firstbranch 710. In this embodiment, Respective ends 7030 and 7050 of thepins 703 and 705 are connected as a composite pin of the second branch710, which may be considered to have a free end as a whole. Thestructure of the composite pin renders a bistable mechanism that iscapable of switching between concave-convex positions in response to anexternal force. Accordingly, a hair styling device as shown in FIG. 7Bcan be produced. For example, the hair styling device may be used as asnap clip. In this embodiment, the pins 701-707 of the workpiece arespaced from each other, the pins 703, 704 and 705 forming the secondbranch 720 are disposed between the pines 702 and 706 forming the firstbranch 710, and the pins 701 and 707 forming the second branch 720 aredisposed outside the pines 702 and 706 forming the first branch 710.Therefore, when the hair styling device is produced as shown in FIG. 7B,the second branch 720 is partially distributed inside and partiallydistributed outside the first branch 710 in a top view, while the secondbranch 720 is in a different layer from the first branch 710 in a sideelevational view. Furthermore, the composite pin is further layered fromthe other part of the second branch 720. When in use, the pins 710, 704and 707 of the second branch is first inserted into hair. Then the pins703 and 705 are forced to switch to a convex position to close and clamphair together with the pins 710, 704 and 707. Afterwards, more hair maybe put inside the open space between the pins 702 and 706 forming thefirst branch 710 and the pins 701, 703, 704, 705 and 707 forming thesecond branch 720, and the first branch 710 is forced to switch to aconvex position to close the open space, thereby securing more hairthereinside.

The configurations of the entire hair styling device may vary with thedistribution of lengths of the pins 703, 704 and 705. As shown in FIGS.7C and 7D, which schematically illustrate an open state, e.g. apreparatory state, and a closed sate, e.g. a working state, the pins 702and 706 forming the first branch 710 are longer than the pins 703 and705 forming the composite pin of the second branch 720, which arefurther longer than the pins 701, 704 and 707 forming the other part ofthe second branch 720. Alternatively, as shown in FIGS. 7E and 7F, whichschematically illustrate an open state, e.g. a preparatory state, and aclosed sate, e.g. a working state, the pins 702 and 706 forming thefirst branch 710 are shorter than the pins 703 and 705 forming thecomposite pin of the second branch 720, which are longer than the pins701, 704 and 707 forming the other part of the second branch 720. It isto be noted that the number and positions of pins in the second branchto be configured as a composite pin may vary with practicalrequirements, and the number and positions of composite pins may alsovary with practical requirements.

FIGS. 8A and 8B schematically illustrate an embodiment of a hair stylingdevice according to the present invention, wherein FIG. 8A schematicallyillustrates a workpiece and FIG. 8B schematically illustrates a hairstyling device produced from the workpiece of FIG. 8A. The workpiece andthe resulting hair styling device are similar to those shown in FIGS. 3Aand 3B, except that there are mini-posts, e.g. teeth or bumps, disposedon surfaces of selected pins, forming an auxiliary structure 370. Inthis embodiment, the mini-posts extend from lateral surfaces of the pinsas the auxiliary structure 370 is integrally formed with the workpiece.Of course, the mini-posts may be provided in alternative ways such asadhesion. By folding the mini-posts of the workpiece toward the spacewherein hair is accommodated, a hair styling device having a structureas shown in FIG. 8B, and switchable between two states as shown in FIGS.8C and 8D can be produced. The auxiliary structure 370 is advantageousin grasping hair. It is understood that any of the previously describedembodiments of hair styling device may be provided with the auxiliarystructure 370, and it is not intended to redundantly describe thedetails.

The workpiece used in the above-described embodiments and otherembodiments modified from those embodiments according to the presentinvention may be formed of any proper flexible material and produced ina variety of ways. The materials, for example, include metal, plastic,paper, bamboo or any other relative rigid material with small thickness.When metal is used, a metal sheet is processed into a single-layerworkpiece defined with a base and a plurality of pins and optionallateral extensive structure and/or auxiliary structure by way ofstamping, and then associated pins are connected to form a hair stylingdevice. Alternatively, the single-layer workpiece defined with a baseand a plurality of pins and optional lateral extensive structure and/orauxiliary structure may also be produced by way of other techniques suchas injection molding of plastic or three-dimensional (3D) printing ofproper material. Particularly when the size of pins, gap between pins,extensive structure from pins, and/or auxiliary structures are small,injection molding or three-dimensional (3D) printing might be a bettersolution than stamping. For example, when producing a hair stylingdevice as illustrated in FIG. 9, it is preferred to use injectionmolding to form a workpiece defined with a base 91, a first branch 910,a second branch 920 and an auxiliary structure 970 since the mini-posts970 can be integrally formed, i.e. directly produced, with the otherparts of the workpiece.

As long as the principles and purposes of the present invention can beachieved, the shapes, sizes and positions exemplified in differentembodiments may be modified and combined according to practicalrequirements. For example, a hair styling device as illustrated in FIG.10 includes various features of the above-described embodiments.

Please further refer to FIG. 11. The embodiment illustrated in FIG. 11is similar to that shown in FIG. 3B except that an auxiliary structure350 is provided. The auxiliary structure 350 includes three pins 311,312 and 313 extending from another side of the base 31, opposite to theother pins 310-304. The pins 311, 312 and 313 may be integrally formedwith the single-layer workpiece defined with the base 31 and the pins301-304, and disposed under the second branch 320 by folding theworkpiece from the base 31. When in use, the auxiliary structure 350 andthe second branch 320 disposed in different layers are both insertedinto hair, and then the first branch 310 is forced to switch to theconvex position to clamp hair together with the second branch 320 andauxiliary structure 350. Since there are two layers of hair clampedinside the hair styling device, better clamping performance can beachieved, particularly for thick hair. The pins of the auxiliarystructure 350 may overlap or stagger from the pins of the second branch320. An overlapping configuration facilitates physical clamping betweenpins, while a staggering configuration exhibits slide-hinderingcapability.

In view of the foregoing, a hair styling device according to the presentinvention is cost-effective, laboring-effective, light and stable foruse.

While the invention has been described in terms of what is presentlyconsidered to be the most practical and preferred embodiments, it is tobe understood that the invention needs not be limited to the disclosedembodiments. On the contrary, it is intended to cover variousmodifications and similar arrangements included within the spirit andscope of the appended claims which are to be accorded with the broadestinterpretation so as to encompass all such modifications and similarstructures.

What is claimed is:
 1. A hair styling device, comprising: a base; and aplurality of pins having respective first ends connected to a first sideof the base, and spaced from each other, wherein the base and theplurality of pins are produced from a single-layer flexible workpiece,at least two of the plurality of pins are connected to each other atrespective second ends opposite to the first ends, thereby forming abistable mechanism that is capable of switching between concave-convexpositions in response to an external force, and at least another two ofthe plurality of pins have free second ends opposite to the first ends,thereby forming a second branch layered from the first branch, and thefirst branch is switched to a concave position relative to the secondbranch to create a space for receiving or releasing hair, and switchedto a convex position relative to the second branch to close the spacefor securing hair.
 2. The hair styling device according to claim 1,wherein all the pins forming the second branch are disposed between thepins forming the first branch.
 3. The hair styling device according toclaim 1, wherein the pins forming the second branch are not all disposedbetween the pins forming the first branch.
 4. The hair styling deviceaccording to claim 1, wherein at least one of the pins forming thesecond branch is a composite pin formed by connecting two of theplurality of pins at respective second ends opposite to the first ends,thereby forming a bistable mechanism that is capable of switchingbetween concave-convex positions in response to an external force. 5.The hair styling device according to claim 1, wherein shapes of the pinsforming the second branch are selected from a group consisting of lines,curves, waves and a combination thereof.
 6. The hair styling deviceaccording to claim 1, wherein adjacent two of the pins forming thesecond branch have respective lateral extensive structures protrudingtoward each other, and the lateral extensive structures are deformableto retain a resilient force when compressed by hair entering the spacebetween the first branch and the second branch, thereby further securinghair in the hair styling device.
 7. The hair styling device according toclaim 6, wherein the lateral extensive structures are thinner than thepins connected thereto, and have conformable shapes to each other. 8.The hair styling device according to claim 6, wherein lateral extensivestructures are produced from the single-layer flexible workpiecetogether with the base and the plurality of pins.
 9. The hair stylingdevice according to claim 1, further comprising mini-posts protrudingfrom a specified surface of the pins forming the second branch.
 10. Thehair styling device according to claim 9, further comprising mini-postsprotruding from a specified surface of the pins forming the firstbranch.
 11. The hair styling device according to claim 10, wherein thespecified surface of the pins forming the second branch is the surfacefacing the first branch, and the specified surface of the pins formingthe first branch is the surface facing the second branch.
 12. The hairstyling device according to claim 10, wherein the mini-posts protrudingfrom the specified surface of the pins forming the first branch are andthe mini-posts protruding from the specified surface of the pins formingthe second branch are produced from the single-layer flexible workpiecetogether with the base and the plurality of pins.
 13. The hair stylingdevice according to claim 1, further comprising an auxiliary structureconnected to a second side of the base opposite to the first side, anddisposed at a side of the second branch opposite to the first branch.14. The hair styling device according to claim 1, wherein thesingle-layer flexible workpiece is made of metal, plastic or paper. 15.A method for producing a hair styling device as recited in claim 1,comprising: providing a metal sheet; stamping the metal sheet to obtainthe single-layer flexible workpiece defining with the base and theplurality of pins; and connecting the at least two pins for forming thefirst branch.
 16. A method for producing a hair styling device asrecited in claim 1, comprising: providing an injection-molded plasticsheet as the single-layer flexible workpiece defining with the base andthe plurality of pins; and connecting the at least two pins for formingthe first branch.
 17. A method for producing a hair styling device asrecited in claim 1, comprising: providing a 3D printed material sheet asthe single-layer flexible workpiece defining with the base and theplurality of pins; and connecting the at least two pins for forming thefirst branch.